Display apparatus

ABSTRACT

Art work formed as colored translucent lines and areas on a design pane is illuminated to provide a changing display as a passageway panel between the design pane and a source of light rotates with the design pane to cause liquid in the passageway panel to flow from a passageway that is between the art work and the source of light to another passageway in the passageway panel where it does not block light from the art work. The art work may be illuminated progressively in any direction and at different speeds and locations by properly positioning the passageways. In the alternative, the liquid may flow from the passageway behind the art work to a separate movable container that is raised by a motor above the passageway and then lowered beneath the passageway while the design pane and passageway panel remain stationary.

Unite States Patent Winslow et al.

[ 51 May 8, 1973 [54] DISPLAY APPARATUS [76] Inventors: Frank Thomas Winslow, 461 l S. Whipple Avenue, Chicago, 111. 60625; Robert Bernard Stanlsh, 3023 S. Farrell, Chicago, 111. 60608 [22] Filed: Feb. 8, 1971 [21] Appl. No.: 113,311

Related U.S. Application Data [63] Continuation-in-part of Ser. No. 865,925, Oct. 13,

1969, Pat. No. 3,638,342.

[52] U.S. Cl ..40/l06.21, 40/33 [51] Int. Cl. ..G09f 13/24 [58] Field of Search .....40/106.21, 33

[56] References Cited UNITED STATES PATENTS 3,071,888 1/1963 Knott ..40/l06.21 X 2,315,240 3/1943 Ashenberg et al ..40/l06.21 3,058,245 l0/1962 Pieters ....40/106.2l 3,388,490 6/1968 Stechemesser ..40/l06.2l 3,613,264 10/1971 Vitka et a1. ..40/l06.2l X

Primary Examiner-Robert W. Michell Assistant Examiner-John F. Pitrelli Att0rneyVincent L. Carney [57] ABSTRACT Art work formed as colored translucent lines and areas on a design pane is illuminated to provide a changing display as a passageway panel between the design pane and a source of light rotates with the design pane to cause liquid in the passageway panel to flow from a passageway that is between the art work and the source of light to another passageway in the passageway panel where it does not block light from the art work. The art work may be illuminated progressively in any direction and at different speeds and locations by properly positioning the passageways. In the alternative, the liquid may flow from the passageway behind the art work to a separate movable container that is raised by a motor above the passageway and then lowered beneath the passageway while the design pane and passageway panel remain stationary. I

8 Claims, 8 Drawing Figures PATENTEDNAY 81915 5.731.412

SHEET 2 [IF 4 PATENTEDHAY 81915 5.731.412

sum 3 OF 4 jimfifwms f u/ E96 M5 fifan s/c PATENTEU HAY 81973 SHEET 4 or 4 DISPLAY APPARATUS This application is a continuation-in-part of the United States patent application, Ser. No. 865,925, filed Oct. 13, 1969, for DISPLAY APPARATUS by Frank T. Winslow and Robert B. Stanish now US. Pat. No. 3,638,342.

This invention relates to display apparatuses and more particularly relates to display apparatuses of the type in which a design is displayed as a liquid flows through the apparatus from one location to another.

In the co-pending United States application Ser. No. 865,925, filed Oct. 13, 1969, by Frank T. Winslow and Robert B. Stanish for Display Apparatus, a display apparatus is disclosed that includes a transparent plastic passageway panel, a lamp, and a design pane having an opaque background with translucent or transparent lines and areas of different colors, shapes and sizes forming a design. The transparent plastic passageway panel includes a plurality of liquid control passageways, light control passageways and reservoirs.

To provide a moving display of a design, an opaque liquid is moved between one location directly between the design and the lamp in a light control passageway of the passageway panel and another location causing the design to be illuminated as the liquid is moved from the light control passageway and to be darkened as the liquid is moved into the light control passageway. The design pane includes a plurality of both narrow and broad lines of different colors and some lines overlie wide light control passageways while other lines overlie narrow light control passageways. The passageways extend in a plurality of different directions within the passageway panel to provide different directions to the motion of the display of the design.

In one embodiment of the display apparatus described in the co-pending application, the liquid is pumped between the passageways in the passageway panel'and an external source of the liquid by a motor that expands and contracts a bellows containing the liquid, which bellows communicates with the passageways in the passageway panel through a conduit. A ventis provided to permit the escape of air as the bellows contracts.

In another embodiment of the display apparatus described in the co-pending application and in this application, a plurality of passageway panels and design panes are mounted together to form a closed group of passageway panels and design panes that are rotatably mounted about a horizontal axis with the passageways of the panels being connected together to form a horizontal rotatable tubular display. As the passageway panels and design panes are rotated, liquid flows from a raised passageway panel to a lower passageway panel to illuminate designs on the raised passageway panel without the use of a bellows.

The display apparatuses described in the co-pending application operate very well. However, the bellows that pumps the liquid into and away from the passageway panel in one embodiment is a part of the display apparatus that is more expensive and more likely to require replacement than other parts. Moreover, under some circumstances, liquid escapes throughthe vent and must be replaced. The second embodiment of the display apparatus disclosed in the co-pending application and forming a part of the subject matter of this division and continuation-impart application does not require a bellows or vent but requires substantial depth and requires that a source of light be mounted within the rotating panels.

Accordingly, it is an object of the invention to provide a novel display apparatus.

It is a further object of the invention to provide a display apparatus of the type in which indicia are displayed by the motion of a liquid without the use of a bellows to move the liquid.

It is a further object of this invention to provide a display apparatus in which a liquid is contained and moved from position to position within the display apparatus to display indicia by gravity rather than by the force of a pump.

It is a still further object of this invention to provide a display apparatus in which indicia is displayed by the flow of a. liquid from one location to another in a panel adjacent to the indicia with the liquid flowing from location to location as the panel is moved.

It is a still further object of the invention to provide a display apparatus with a sealed liquid system to display indicia as the liquid is moved from place to place in the sealed system.

In accordance with the above and further objects of the invention, a display apparatus is provided having a design pane, a passageway panel, and a lamp. The design pane has an opaque background with translucent or transparent lines and areas of different colors, shapes and sizes to form one or more designs. The word design, as used herein, includes all types of indicia for display such as names, words, and pictures. The passageway panel is attached to the design pane and includes a plurality of liquid passageways, with some of the passageways overlying designs and other passageways overlying opaque portions of the design pane. The passageways contain air and an opaque fluid that is heavier than air such an opaque liquid.

To provide a moving display, the design pane and passageway panel are rotated while the lamp radiates light upon the back surface of the passageway panel. The passageways in the passageway panel are positioned so that, as the passageway panel and design pane rotate, liquid flows between the passageways behind the design and passageways behind the opaque portion of the design pane. While the passageways behind the design are full of the liquid, they block light from the design, and while the passageways behind the design are being emptied, portions of the design are uncovered, whereby the design is progressively illuminated. The passageways may be so positioned that the designs are uncovered by the liquid in a selected direction and at a selected speed. Moreover, the lines may be uncovered by bubbles flowing across the design and special luminescent effects may be obtained by ultraviolet light.

In another embodiment, the design pane and passageway panel are stationary. The liquid flows between an external movable liquid source and the passageways as a motor raises and lowers the source of the liquid so that the liquid flows into the passageway panel and away from the passageway panel by gravity. In this embodiment, as in the previous embodiment, the designs are illuminated and displayed as the liquid is moved to and from passageways aligned with designs.

The apparatuses of this invention have the advantages of being easily fabricated, being relatively small size, and operating by the flow of a liquid caused by gravity rather than by a pump. Because of these advantages, the display apparatuses are inexpensive and durable. Moreover, since the liquid systems are sealed, the apparatuses have the advantage of not requiring the replacement of liquid that has evaporated or spilled.

The above-noted and other features of the invention will be better understood from the following detailed description when considered with reference to the accompanying drawings in which:

' FIG. 1 is an exploded perspective view of an embodiment of the invention;

FIG. 2 is an elevational view of the display apparatus of FIG. 1 as it appearsin one mode of operation;

FIG. 3 is an elevational view of another embodiment of the invention;

FIG. 4 is a side view of the embodiment of FIG. 3;

FIG. 5 is a side view of another embodiment of the invention;

FIG. 6 is an elevational view of the embodiment of FIG. 5;

FIG. 7 is a perspective view of another embodiment of the invention; and

FIG. 8 is a perspective view of still another embodiment of the invention.

STRUCTURE OF FIRST EMBODIMENT In FIG. 1, an exploded perspective view of a display apparatus 10, which is an embodiment of the invention, is shown having a design pane 12, a passageway panel 14, a motor 16, and a lamp 18. The design pane 12 is attached to the front surface of the passageway panel 14 with both the passageway panel 14 and the design pane 12 being rotatable by the motor 16. The lamp 18 is located on the opposite side of the passageway panel 14 from the design pane 12 to shine light therethrough.

The design pane 12 has an opaque background and three designs formed of translucent or transparent lines and areas on the opaque background, which are: (l) a border design 20; (2) a pictorial design 22 indicated by the word, design; and (3) five letters 24 indicating the nameof a brand. The designs are shown as black lines in FIG. 1 for clarity even though in practice they are translucent or transparent lines. The design 22 may be any type of art work, either in black and white or color.

The passageway panel 14 has a flat raised background surface 26 and a plurality of recessed portions 28 forming passageways of two types, which are: (1) liquid control passageways and (2) light control passageways. The light control passageways and liquid control passageways have the same structure but serve different purposes as will be explained hereinafter.

The passageway panel 14 may be formed in any convenient manner and of many different materials but is economically formed by injection molding or by vacuum-forming or die stamping a transparent plastic sheet to form the recessed portions 28 and by covering the surface of the sheet having the recessed portions 28 in it with a flat transparent plastic sheet that is attached to the raised background surface 26 to seal the recessed portions 28. Moreover, large-volume reserdesign pane 12 at a central location to the shaft of the voirs may be formed by increasing the depth of the passageways, particularly if the passageway panel is formed in an injection molding process. Although it is preferable to seal the recessed portions 28 with a separate transparent sheet, the design pane 12 may serve this purpose as well. A liquid is inserted into the passageways before they are sealed by the top sheet of plastic or, after the top sheet is applied, through small holes that are later sealed.

The design pane 12 fits over the surface of the passageway panel 14 with the designs 20, 22, and 24 overlying some recessed portions 28, the remainder of the recessed portions 28 being covered by opaque areas of the design pane 12. The portions of the recessed portions 28 that are aligned with the designs 20, 22 and 24 are called light control passageways and the remainder of the recessed portions 28 are called liquid control passageways.

The recessed portions 28 form two closed circuits in the passageway panel 14, an inner circuit and an outer circuit.

The inner circuit includes two light control passageways, which are: (1) five large recessed portions 30A 30E, each of which is aligned with a different one of the five translucent portions forming the design 24 in the design pane l2; and (2) a single large recessed portion 32 aligned with the pictorial design 22 in the design pane 12. The light control passageways 30A 30E and 32 are connected by liquid control passageways.

The outer circuit includes: (1) a large area 34, the top portion of which is a light control passageway and the bottom portion of which is a liquid control passageway or reservoir, and (2) a narrow circular light control passageway 36 connecting the two sides of the large area 34. The border design 20 overlies the light control passageways of the outer circuit.

An opaque liquid is in the inner and outer circuits 28. There is not sufficient liquid in either of the circuits to completely fill the passageways but only enough liquid so that when the display apparatus 10 is located vertically as shown in FIG. 1, the top portions of the passageways are drained of liquid and the bottom portions are filled with liquid.

The motor 16, which is any type of motor but preferably an electric motor that rotates at approximately 1 revolution per minute, rotates the passageway panel 14 and design pane 12 about a central point. In the embodiment of FIG. 1, the passageway panel 14 and design pane 12 include an aperture accommodating a threaded portion of the shaft of the motor and held thereto by a nut and lock washer. However, any suitable means for mounting the design pane 12 and passageway panel 14 may be employed. Moreover, it is not necessary to mount the passageway panel 14 and motor 16, but it may be located at an offset location,

where desirable, to control the proper flow of liquids where these are not blocked by an opaque liquid in aligned light control passageways. The light, of course, is blocked by the opaque portions of the design pane 12.

In the embodiment of FIG. 1, the passageway panel 14 and the design pane 12 are rotated in a counterclockwise direction (facing FlG. 1). With this direction of rotation, liquid is drained from the leftmost light control panels first. For example, liquid is drained from the light control passageway 30A before being drained from the light control passageway 308.

To avoid turbulence during the draining of the liquid, the narrow passageways such as 36 connecting the larger passageways such as 34! communicate with the larger passageways nearer to the center of rotation on the trailing side (the side which arrives at a stationary point last during rotation) and on the radially most distant point on the leading side (the side that first reaches a stationary point) in the direction of rotation. This permits the liquid to be drained from the bottom of a light control area as it is raised during rotation and to enter from the bottom of the area as it is lowered so as to reduce the turbulence in the liquid.

Moreover, where the pressure head between diametrically opposite portions of the passageways is small and one portion has passageways of relatively small cross-sectional area such as in the inner circuits, an enlarged portion 37 is provided in one of the smaller liquid control passageways to enable the air and liquid to flow more freely. Air bubbles that are trapped in the narrow passageway during transportation of the display apparatus in a horizontal position are removed during the first few revolutions of the passageway panel by the free flow of liquid and air through the enlarged portion 37 to reset the panel for proper operation.

In FIG. 2, an elevational view of the display apparatus of this invention is shown with a cover plate 38 positioned in front of the design pane 12 to block the lower half of the display apparatus from a viewer. The coverplate 38 need not be included but serves to block from view all of the design pane except the illuminated design at the top portion of the display 10. With this arrangement, the cover plate 38 includes a stationary design 39.

As best shown in FIG. 2, the design 24 is smaller in size than the light control passageways 30A 30E that it overlies with a portion of the light control passageways being covered by the opaque portion of the design pane 12. This is generally true of designs although not absolutely necessary for operation. The light control passageways may be of the same size as the design portions on the design pane but, by making them larger, the fabrication of the apparatus is simplified by the reduced tolerances in forming the passageway panel 14. Moreover, different design panes may be used with the same passageway panel 14 and some of these design panes may require larger light control passageways than others. A light control passageway serves to control and animate any design of a smaller area than the light control passageway with which it is to be aligned.

GENERAL OPERATION There are several modes of operation that are possible with the display apparatus 10. Some of these modes of operation are substantially the same as modes of operation described in the co-pending United States patent application Ser. No. 865,925 filed Oct. 13, 1969 by Frank T. Winslow and Robert B. Stanish for Display Apparatus. These modes of operation may be utilized with the display apparatus of FIG. 2 with slight modifications as well as with the apparatus disclosed in the co-pending application.

Not all of the modes of operating the display apparatus of H68. 1. and 2 will be described here, but first a general mode of operation will be described and then the more important alternate modes of operation will be briefly described.

ln the general mode of operation, the design pane 12 is fastened in front of the passageway panel 14. The lamp 1% is illuminated from behind the passageway panel 14 while the passageway panel 14 and the design pane 112 are rotated together in a counterclockwise direction as shown by the arrow in FIG. 2.

As the passageway panel and design pane rotate, the liquid in the light control and the liquid control passageways drains from. the top of the passageway panel to the bottom. For example, as the design 24 approaches the top, liquid drains from the light control passageway 30A downwardly through the light control passageway 3693. As the liquid is drained from the passageway 30A, light from the lamp l8 shines through the circle displaying the letter 18. Similarly, as the design pane l2 and passageway panel 1.4 continue to rotate, liquid is drained from the light control passageways 3613B, IlllC, 30D and 30E in succession, enabling light to shine through the design to display the word, BRAND or any other word forming the design 24. At the same time, liquid drains from the light control passageways 34 and 36 behind the border 20 to cause the border to be displayed.

When the passageway panel 14 and design pane 12 have rotated so that the design 24 is near the bottom, the liquid drains from the light control passageways 32 and 36 to enable light to shine through the design 22 and the border that is being rotated toward the top of the display. With this arrangement, designs are'continually displayed with animation at the top of the display apparatus 110. The designs may include any type of art work including art work of different colors and art work with fine and thick lines.

Several special effects are available because the light control and liquid control passageways are of difierent sizes and shapes from the design or words to be displayed, which efiects are: (l) the speed with which a line is displayed is varied in proportion to the size of the light control passageway underlying it since a larger passageway is emptied more slowly than a small passageway; (2) time delays before starting the display of a line are provided by interposing a large liquid control passageway in the passageway panel immediately before the light control passageway that is to start the time delay; (3) horizontal lines are illuminated at the same time across their entire length and the lines slightly at an angle from the horizontal are illuminated very rapidly when a single large area light control passageway underlies the horizontal or substantially horizontal line; and (4) a plurality of individual small lines are displayed at the same time if they are in a horizontal line overlying a single wide light control passageway.

The rotatable display apparatus shown in .FIGS. 1 and 2 have the further advantages of providing a sealed system for the liquid so that it need not be replenished and of enabling it to be operated simply by standard commercial electric motors. With this mechanization,

an inexpensive reliable unit may be fabricated.

While a display apparatus that continually rotates in one direction has been described, it is obvious that a passageway panel and design pane that rotates first in one direction and then in another to cause the liquid to flow between two light control passageways or between a light control passageway and a liquid control passageway can be constructed. Moreover, still other types of motion may be used to cause the liquid to flow within the passageways to animate a design.

SECOND EMBODIMENT In FIG. 3, an elevational view of a second embodiment is shown, in which embodiment the design pane 12 includes five transparent or translucent lines 40, 42, 44, 46, and 48. These lines are shown on the design pane 12 in FIG. 3 to illustrate special effects of particular importance that are obtainable with the invention, which special effects will be described below under separate headings.

The passageway panel for the embodiment of FIG. 3 includes passageways under each of the lines 40, 42, 44, 46 and 48'of the design pane 12, which are: (l) a passageway 50 under the line 40 extending along its length and connected at its leading side to another passageway 52 that opens into a large passageway reservoir 54 with the reservoir 54 being radially inward from the passageway 50 and to its trailing side; (2) a passageway 56 in the shape of an 8 passes beneath the lines 42 and 44 of the design pane 12, with the passageway 56 having a section in one of its loops of the 8 underlying the line 42 and a portion in the second of the loops of the 8 underlying the line 44; (3) a passageway 58 having an enlarged reservoir section near the center of the passageway panel and an arm extending radially outwardly at an angleto underlie the line 46 in the design pane with a restricted portion 60 between the large area and the arm that underlies the line 46; and (4) a passageway 62 having an arm underlying the line 48, which arm opens into an enlarged area that is located radially outwardly and to the trailing side of the arm. The passageways that are longer have an air return path to form a complete circuit for the flow of air and liquid but the shorter ones do not. In a short, wide passageway the liquid and air are able to pass each other in the same portions of the passageway without undue turbulence.

In FIG. 4, a side view of the embodiment of FIG. 3 is shown having an ultraviolet lamp 64, an incandescent lamp 66, a motor 68, a design pane l2, and a passageway panel 14. The motor 68 rotates the design pane 12 and the passageway panel 14 while the lamp 66 radiates light upon the back of the passageway panel 14 in the same manner as in the embodiments of FIGS. 1 and 2. In one mode of operation, the ultraviolet lamp 64 irradiates ultraviolet light upon the face of the design pane 12.

To permit the passageway 56 to cross and form the two loops of the FIG. 8, a portion 72 passes another portion behind the panel as a tube that communicates with the passageway 56in the passageway panel at two locations 74 and 76 on either side of the portion it crosses, being cemented in place to permit the liquid to flow through the tube behind the passageway panel and around the portion of the passageway panel 56 that is recessed into the passageway panel and back into the passageway panel. Similarly, a tube 78 in the passageway 56 passes around the outside of the panel and communicates with the passageway 56 to permit the passageway 56 to pass the passageway 52 in the panel.

CHANGING THE DIRECTION OF DISPLAY In operation, the design pane 12 and passageway panel 14 in the embodiment of FIGS. 3 and 4 rotates in a counterclockwise direction as shown in FIG. 3 by the arrow 81. With this direction of rotation, lines and areas normally are drawn from left to right at the top of the design pane as the leading portion of the design is raise in the normal rotation of the design pane and passageway panel to drain the liquid from the leading end of the design to the trailing end.

The designs 40 and 42 are examples of two designs which are drawn from right to left at the top of the design pane rather than from left to right with a counterclockwise rotation. Thus they are drawn from the trailing edge to the leading edge rather than from the leading edge to the trailing edge as in the normal direction.

As the design 40 is raised, the liquid drains from the right end of the passageway 50 to the left, through the passageway 52 and into the large area 54, permitting light to illuminate the design 40 from right to left. Since the passageway 52 and 54 in the passageway panel 14 are covered by opaque portions of the passageway pane, light does not pass through them. As the design 42 is raised, it is displayed from left to right with the liquid draining through the tubes 72 and 78 in that order before flowing through the passageway under the design 44.

As the design 44 is raised, it is displayed in the normal direction from left to right with the liquid draining through the passageways 56 toward their trailing edge even though it overlies a passageway in the same circuit as the passageways that control the display of the design 42. In this manner, the passageway 56 causes the design 44 to be displayed in the normal manner from left to right and the portion of the design 42 to be displayed in the opposite direction.

The designs 40 and 42 illustrate that designs may be displayed in any direction on the same design pane. Moreover, difierent lines may be written in the same design area extending either upwardly or radially inwardly to provide further variations in the direction of the display of the lines.

Besides providing different directions for the display of designs near the top of the cycle of rotation, the design pane 12 and passageway panel 14 are also able to provide for a design to be erased near the top of the cycle of rotation and displayed near the bottom of the cycle of rotation. The design 4.8, for example, is displayed at the bottom and right-hand side of the design pane 12 and passageway panel 14. However, as it reaches the top of the cycle of rotation, liquid from the large passageway 62 that is radially outward from the design 48 flows into the passageway beneath the design 48 to erase it at the top and left side of the display apparatus.

The passageway 62 and the design 48 provide an animated display near the bottom of the design pane by illuminating the design there or provide an animated display near the top of the design pane by causing the design to be erased there.

The embodiments of FIGS. 1-4 illustrate that the passageways may be arranged in different ways. The

passageways of the embodiments of FIGS. 1 and 2 extend around and encircle the center of rotation while the passageways of the embodiments of FIGS. 3 and 4 do not. In the embodiments of FIGS. 3 and 4, the passageway 56 extends in two loops for more than 180 degrees about the center of rotation while the passageways 50, 54, 58 and 62 extend over fewer degrees about the center of rotation. The relative locations and sizes of the light control passageways and liquid control passageways are chosen to display a design at a selected location and to draw it in a selected direction.

BUBBLING EFFECTS A special effect can be obtained by pennitting bubbles to flow through a design as it is displayed. The air bubbles provide a path for light and appear luminous as they move across the design.

The design 46 is arranged over the passageways 58 for this purpose. As the design 46 is raised, air within the reservoir 58 is slowly released through the restricted orifice 60 and bubbles pass through the passageway underneath the design 46 to slowly display it. The length of time of the bubbling is controlled by the length of the passageway under the design 46 and the size of the passageway extending radially beyond the design 46 that receives the air from the bubble. If a large reservoir is located radially outwardly from the design 46 in the passageway to accommodate a large amount of air and the restricted orifice 66 is sufficiently small, the design 46 is not uncovered but is only displayed by the passage of bubbles across it.

ULTRAVIOLET LIGHT EFFECTS Further special effects are obtainable from the embodiment of FIGS. 3 and 4 by illuminating the lamp 64 so that ultraviolet light from the lamp 64 is irradiated upon the design pane 12.

The ultraviolet light may co-operate with the panel in three ways, which are: (l) by causing a design painted with fluorescent dye to be displayed on the background opaque areas of the design pane l2; (2) by causing fluorescent dye within the liquid in the light control passageways to emit light; and (3) by causing a design painted on the light control passageways to be dis played in different colors as liquid is withdrawn from the passageways. The ultraviolet lamp 64 may be alternately illuminated and extinguished or may be illuminated continually. This mechanization provides greater variety to the display.

THIRD EMBODIMENT OF DISPLAY In FIG. 5, a side view of a third embodiment is shown having a front design pane 12, a front passageway panel 14, a back design pane 80, and a back passageway panel 82. Both front and back design panes and passageway panels are rotated by the motor 68 in a clockwise direction as shown by the arrow 83 in FIG. 6 and receive radiation from the lamp 66 except where the light is blocked by an opaque portion of a design pane or passageway panel behind it.

In FIG. 6, an elevational view of the embodiment of FIG. 5 is shown having a first design 843 on the design pane 8d. The design 84 is opaque and of a different color from the background on the design pane adjacent to it, which background is also opaque. The design pane i2 plays no part in the display of the design and is considered transparent over this area or omitted altogether as far as the design 84 is concerned. The passageway panel 14 includes a liquid passageway 87 having a liquid control portion covered by an opaque portion of the design pane l2 and a light control portion aligned with and over the design 84.

A second design 86 includes a first portion 88 in the shape of a letter B on the first design pane 12 and a second portion 90 shaped as a circle around the letter B in the second design pane 80. The design pane 12 also includes a transparent portion within the circle 90 so that the letter B is visible and displayed by light when there is no intervening liquid.

To control the display of the letter B, the first passageway panel 14 includes four interconnected passageways, which are: (l) a liquid control passageway 92; (2) a light control passageway 594 forming a circle behind the letter B design 88; (3) a liquid control passageway 96 on the opposite side of the light control passageway 94 from the liquid control passageway 92; and (4) an air return passageway 93. The second passageway panel $2 includes a light control passageway 98 behind the circle design 90 and an interconnected liquid control passageway 160 located in proximity to the liquid control passageway 96.

A third design 102 is formed on the design pane 12 within the design pane 80 having a transparent portion beneath it. A first light control passageway 104 in the first passageway panel 14 and a second light control passageway 106 in the second passageway panel 82 are behind the design 102. A liquid control passageway 108 communicates with the light control passageway I in thepassageway panel 14 on one side of the design 102 and a'liquid control passageway 110 communicates with the light control passageway 106 in the passageway panel 82 on the other side of the design 102.

The embodiment of FIGS. 5 and 6 may be operated in several modes and the most important of these modes will be discussed immediately below under separate headings.

DAYLIGHT OPERATION The embodiment of display apparatus shown in FIGS. 5 and 6 may be operated without the use of lamps using only the passageway panel 14 and the design pane 80. When operated in this manner, the remainder of the apparatus is unnecessary. Therefore, the actual apparatus for daylight operation when the display apparatus is to operate only in this mode is simpler than the embodiments shown in FIGS. 5 and 6. On the other hand, one design in a display apparatus may be operated in the daylight mode and another may be operated with a lamp 66 positioned behind it.

The design 84 and the passageway 87 operate in the daylight mode. For use in this mode of operation, the design pane 80 in the vicinity of the design 84 is a positive with the design 84 being formed of lines and areas that are not translucent or transparent but are opaque and colored. The background of the design pane surrounding the design 84 is of the same color as the liquid that fills the passageway 87.

In operation, the design 84 on the design pane 80 is visible from the front of the display apparatus whenever there is no liquid within the portion of the passageway 87 covering it. This is true because the passageway panel 14 covering it is of a transparent plastic so the design on the design pane 80 shows through it. As the design 84 is raised along the left-hand side of FIG. 6 by the rotation of the passageway panel 14 and design pane 80, liquid flows from the liquid control portion of the passageway into the light control portion of the passageway 87 over the design 84. When liquid is over the design 84, the design 84 is not visible. As the design 84 is lowered along the right-hand side of FIG. 6, liquid is drained from the light control passageway into the liquid control passageway to uncover the design 84 for display.

Although in the embodiment of FIG. 6, the design 84 is positioned to be uncovered when it is lowered along the right-hand side of the display apparatus, it may be positioned to be covered and uncovered at other positions by changing the relative positions of the light control and liquid control passageways. Accordingly, the display 84 may be shown at either the top or the bottom of the display apparatus.

OVERLAPPING SEQUENCES By using both passageway panels 14 and 82, two

sequences of a design which are independent in time but overlapping are drawn by the display apparatus.

With this construction, a moving design is under the control of any of three arrangements of light control passageways, which are: (1) only under the control of the light control passageways in the front passageway .panel 14 because the translucent or transparent lines and areas overlie or are aligned with these passageways on both the front design pane 12 and the rear design pane 80 but no light control passageways in the passageway panel 82 are aligned with the same translu cent or transparent areas; (2) only under the control of the light control passageways in the back passageway panel 82 because there are transparent or translucent lines and areas aligned with these light control passageways on both the front design pane 12 and the design pane 80, but no light control passageways in the passageway panel 14 are aligned with the light control passageways in the panel 82; and (3) under the control of aligned light control passageways in the front and back passageway panels 14 and 82 because there are translucent or transparent lines and areas aligned with light control passageways on both design panes l2 and 80.

When the design is under the control of only one passageway panel, whether the front passageway panel 14 or the rear passageway panel 82, the mode of operation is similar to that described in connection with FIGS. 1-4 and will not be described in detail here. Instead, the operation of the embodiment of FIGS. 5 and 6 will be described as it applies directly to a display that is under the control of aligned light control passageways in the front and back passageway panels 14 and 82.

In FIG. 6, the design 88 of the letter 8" is controlled by the front passageway panel 14 and the design of the circle 90 around the letter B is controlled by the back passageway panel 82. As the designs 88 and 90 are raised over the top and lowered by the rotation of the passageway panels 14 and 82, liquid flows from the light control passageway. .98 into the liquid control passageway in the passageway panel 82 and from the liquid control passageway 92 through the light control passageway 94 and into the liquid control passageway 96 in the passageway panel 14. The air return passageway 93 is included because of the long path for the flow of liquid. With this arrangement of passageways, the light control passageway 98 in the rear passageway panel 82 is drained of liquid before the light control passageway 94 in the passageway panel 14 because the liquid in the light control passageway 94 is replenished by liquid from the liquid control passageway 92 as the liquid flows into the liquid control passageway 96. Accordingly, light shines from the lamp 66 through the design panes 12 and 80 around the light control passageway 94 to display the design 90 in the form of a circle with a dark disc being shown aligned with the light control passageway 94. Later, the light control passageway 94 is'drained of liquid to cause the design 88 in the form of a letter B to be displayed within the circle 90.

The passageway panels 14 and 82 cooperate together to cause a design to be displayed from one end while it is being erased from the other in addition to successively displaying two portions as was the case with the designs 88 and 90. The design 102 is arranged to be successively displayed from one end while it is erased from the other.

As the design 102 approaches the top of the rotating path, the liquid control passageway 108 is full while the light control passageway 104 is empty in the passageway panel 14. The light control passageway 106 is being drained of liquidwhich flows'into the liquid control passageway in the passageway panel 82. As

the liquid flows from the light control passageway 106 into the liquid control passageway 110, the design 102 is exposed and displayed starting from the edge that is leading in the clockwise rotation of the display apparatus.

Before the design 102 is entirely exposed, the liquid control passageway 108 reaches a height above the light control passageway 104 causing liquid to be drained from the liquid control passageway 108 into the light control passageway 104. This liquid begins to cover the design 102 starting from the trailing edge in the clockwise direction of rotation of the design panes and passageway panels. Accordingly, the design 102 is simultaneously exposed from one end and erased from the other.

A similar arrangement may be constructed to, cause the design to be exposed and then erased, at the bottom of the rotational path of the design apparatus or to be exposed and erased at the sides of the design apparatus by including an appropriate delay between the draining and filling of the light control passageways in separate liquid control passageways that are located on either side of the light control passageway.

COLOR MIXING In each of the embodiments, another special effect is obtained through the use of lines and areas of the designs that are translucent and colored and a liquid that is not opaque nor of the same color as the opaque portions of the design panes. The liquid is selected to have a color that, when mixed with a color of the translucent lines and areas of the design, provides the same color as the opaque portions of the outermost design pane or is in itself opaque.

With this arrangement of colors, the lines and areas of the design appear in colors contrasting with that of the background as the liquid is drained from the passageway panel. This arrangement and choice of colors enables the background of the design to be colored and the lines and areas to be drawn into the design in a contrasting color.

ln the embodiment shown in FIGS. and 6 having two separate passageway panels 14 and 82, greater variations are possible in the color of the design through the use of color mixing than in the embodiments of FIGS. 1-4. In portions of a design in which the from design pane 12 and the rear design pane 80 have aligned translucent or transparent areas and lines with only one of the two passageway panels 14 and 82 having an aligned light control passageway, a variation of two colors is possible. One of the two colors is formed by the combination of colored liquid and the colors of the translucent design panes and the other color is formed only by the combination of colors in the aligned translucent portions of the two design panes.

In the portions of the design in which there are aligned light control passageways in both the passageway panels 141 and 82 and aligned translucent areas and lines in both the front design pane 12 and the rear design pane 80, three colors are obtainable. The first color is obtained by a mixture of the colors of both colored liquids in the light control passageways with the colors of the design panes, and this color matches the background. The second color is formed by the color of one of the liquids in one of the light control passageways and the colors of the translucent areas and lines on both of the design panes, and this color is formed after one of the liquids has been drained from the display apparatus at that location. The third color is formed only by the combination of the colors of the light control passageway 98, the letter B design 88 appears in another color and the background in still another color because the B design 88 is still influenced in color by the color of the liquid in the light control passageway 94. After the liquid has been withdrawn from the light control passageway 94, the B appears in still another color because it is now only influenced by the color of the design 88 on the design translucent areas and lines of the design panes after both liquids have been withdrawn from the display apparatus at that location.

For example, in one embodiment the design pane 12 (FIG. 6) has a translucent disc area of one color overlying the light control passageway 94 with a letter 13 design 88 of another color in its center and the design pane 80 has a translucent disc-shaped area with the circle 911 overlying the disc-shaped light control passageway 98. The liquids in the passageways of the panels 14 and 82 that are to flow through the light control passageways 94 and 98 are selected to pass light with sufficiently small attenuation to permit the light to illuminate the front design pane after passing through both liquids and both design panes.

In operation, the light from the lamp shines through the liquids in two light control passageways 94 and 98 and through both design panes to provide a colored letter B and a colored circle 90 on backgrounds of different colors. When the liquid is drained from the pane 12 whereas the circle design 91) remains the same color as before the liquid was drained from the light control passageway 94.

FOURTH EMBODIMENT In FIG. 7, another embodiment of the invention is shown. In this embodiment, a stationary panel 112 has a passageway panel 114 and a design pane 1 16. Behind the stationary panel 112 is a lamp 118, a motor 120, an eccentric 122, and a container for liquids 124.

The design pane 116 is opaque except for a translucent area 136 that includes a design, shown as a letter B. The passageway panel 114 is transparent and includes a liquid passageway 128 behind the design and connected to the liquid container 124 by a bottom flexible tube 130 and a top flexible air return tube 131.

To provide a liquid to the passageway 128 and to withdraw the liquid therefrom, the motor rotates a linkage 132 connected at its outer end by a pin and slot connection to a lever 134 of the eccentric 122. The lever 134 is pinned to the frame of the display apparatus at one end and fastened to the liquid container 124 at its other end, whereby the liquid container 124 is raised and lowered as the motor 120 rotates the arm 132.

In operation, the motor 120 causes the lever 134 to raise the liquid container 124. As the liquid container 124 is raised, the passageway 128 is filled with an opaque liquid so that light from the lamp 118 is blocked from the design pane. While the liquid is in the passageway 128, there is no design visible from the design pane 116.

As the motor 120 continues to rotate, the liquid container 124 is lowered so that the liquid passes from the passageway 128 through the flexible tube 130 into the liquid container 124. As the liquid drains from the passageway 128, light from the lamp 118 shines through the passageway panel 114 and the design of a letter B on the design pane 116 to cause the letter B to be drawn from its top to its bottom.

Although a simple design of a letter B has been illustrated, other designs may be provided on the design pane 16 for display. Similarly, many special display effects are possible such as those described in United States co-pending application Ser. No. 865,925, filed Oct. 13, 1969, by Frank T. Winslow and Robert B. Stanish for Display Apparatus. Moreover, the special display effects obtainable in the embodiments of FIGS. 1-6 are obtainable in a similar manner in the embodiment of FIG. 7.

The unique feature of the embodiment of FIG. 7 is the sealed liquid system that causes liquid to flow to and from the passageway panel 114 by gravity without the need for a bellows type pump. The mechanism for moving the liquid is inexpensive and durable because of its simplicity and because it utilizes a sealed liquid system.

In FIG. 8, still another embodiment of the invention is shown. This embodiment of the invention is described in the aforementioned co-pending applica tion of which this application is a division and continuation-in-part as well as being described in this application. 1

In the embodiment of FIG. 8, a plurality of panel sections 138, three of which 138A 138C are shown in FIG. 8, are fastened around the outside of a transparent plastic cylinder 140. Each of the panel sections 138 includes a passageway panel section 142 and a design pane section 144, with three of the passageway sections and design pane sections being indicated at 142A 142C and 144A 144C, respectively. The passageway sections are fastened to the outer surface of the transparent plastic cylinder 140 and the design pane sections are fastened to the outer surface of the passageway sections.

Each of the passageway sections 142 includes a corresponding passageway 146, with the passageways 146A 146C being shown in FIG. 8. The passageways of each, of the panels communicate with the passageways in the adjacent panels around the transparent cylinder 140 through relatively narrow connecting passageways so that, for example, the passageway 146B communicates at one end with the passageway 146A and at its other end with the passageway 146C. The passageways 146 include sufficient opaque liquid so that the passageways in the bottom third of the passageway sections are filled with the opaque liquid when the cylinder is not rotating.

Each of the design pane sections 144 includes a translucent or transparent design area 148, with the design areas 148A-148C being shown in FIG. 8. These design areas may include designs of any kind including lines of any size, shape and color. The design sections are each positioned over a passageway and are smaller than the passageway, with the remainder ofeach of the design panes being opaque to light. v

The passageway sections 138 may be separately formed with separate passageways and then fastened to the transparent cylinder 140 with "their passageways interconnectedor they may be formed together as an integral unit as one continuous passageway panel that is flexible and then. fastened around the transparent cylinder 140 with the end passageways connected.

' In the preferred embodiment, the passageways 146 of each passageway section are connected to the passageways of adjacent passageway sections to form a continuous passageway around the cylinder 140 so that the liquid always remains at the bottom and front of the cylinder. However, it is not necessary to have continuous passageways around the cylinder 140 but passageway sections may be connected to have a continuous passageway thatonly extends part way around the cylinder, in which case only a portion of the surface of the passageway sections is able to present a design which is increasingly illuminated on the design pane as liquid is drained from its passageways because a portion of the passageways must serve as a reservoir for the liquid as it is raised by the rotation of the cylinder. The portion that serves as a reservoir may display a design that is erased as it is raised or a design that is fixed in location onthe design pane such as a design with no passageway behind it so that light will always shine through the translucent area where the design is located.

To support the transparent plastic cylinder 140, a stand is provided having a flat horizontal base section 152 with two upwardly extending end sides 154 and 156. A horizontally positioned shaft 158 is rotatably supported within bearings by each of the two side plates 154 and 156. At each end of the transparent plastic cylinder 140, there'are a plurality of spaced apart radially extending arms 160 ending in a central ring through which the shaft 158 passes. The rings are fastened to the shaft to rotate therewith.

To rotate the transparent cylinder 140 and the panel sections 138, an electric motor 162 is provided having its output shaft 164 coupled to the shaft 158 at 166. The motor 162 rotates at approximately one revolution per minute to rotate the cylinder 140 and panels 138 for display purposes.

To provide light within the cylinder 140, two conductive rings 168 and 170 are mounted to the shaft 158 for rotation therewith and connected by means of brushes to the electrical wires 172 and 174, respectively, to energize the conductive rings. A plurality of fluorescent lamp fixtures 176 support a plurality of fluorescent lamps and are mounted to the radially extending arms 160. The fixtures 176 are electrically connected to the conductive rings 168 and 170 to provide energization of the lamps 178.

In operation, the motor 162 is energized to rotate the shaft 158 that extends through the transparent cylinder 140. As the shaft 158 rotates within the stand 150, the transparent cylinder 140 and the panel sections 138 are rotated since they are connected to the shaft 158 by the inwardly extending arms 160. The shaft 158 rotates in the direction shown by the arrow so that panel sections 138 at the bottom of the cylinder are raised to face a viewer looking into the display as shown in FIG. 8. As the panels are raised, they raise some of the liquid within the passageways 146 because the connections between the passageways are relatively narrow. The speed of rotation of the shaft 158 and the construction of the passageways are such that the design 148 that is vertical, such as design 148B in FIG. 8, overlies a passageway that is being drained of liquid. The designs at the bottom of the cylinder overlie passageways that are filled or are being filled with liquid flowing from the vertical passageways to the bottom passageways.

In practice, the front 'ofthe display apparatus is covered except for the central portion through which a vertical design shows. This vertical design is being drained of liquid and displayed to the viewer.

While the display is operating, an alternating voltage is applied to the wires 174 and 172. This voltage is received by the lamp fixtures 176 to illuminate the lamps 178. Light from thelamps 178 shines through the designs where not blocked by liquid in the passageways 146. The passageway panel that is displaying a design, such as 1383 in FIG. 8, shows the design being raised and at the same time being illuminated in the direction of the passageways as the liquid drains from the passageways in that panel to the passageways in lower panels.

With this arrangement, no vent is needed since there is no bellows nor pump. The display is animated by gravity. Moreover, different designs are brought in front of the viewer at different times for animated display in a continuous sequence.

This embodiment and each of the other embodiments of the invention have several advantages, which are: (1) there is no escape of liquid through a vent orifice; (2) there is no bellows which is subject to greater wear than other parts of the apparatus; and (3) the apparatus is simple and inexpensive to fabricate and to operate.

Although an embodiment of the invention has been described with some particularlity, many modifications and variations of the embodiment are possible within the light of the above teachings. It is therefore to be understood that, within the scope of the appended claims, the invention may be practiced otherwise than as specifically described.

What is claimed is:

1. A display apparatus comprising:

a viewing surface having a design background;

at least one continuous circuit formed of a material capable of passing light;

said conduit being partly filled with a fluid capable of of blocking at least some frequencies of light;

a design formed of lines and areas upon a design background;

said lines and areas being aligned with at least a portion of said conduit;

means for changing the position of said conduit at different times so that at one time a first portion of said conduit is above a second portion and at another time a second portion of the conduit is above the first portion;

a panel adjacent to the viewing surface;

a first portion of said continuous conduit being within said panel and a second portion being external to said panel;

said means for changing the position of said conduit including means for raising and lowering the portion of said conduit external to said panel while said panel is stationary.

2. A display apparatus comprising:

a viewing surface having a design background;

at least one continuous conduit formed of a material capable of passing light;

said conduit being partly filled with a fluid capable of blocking at least some frequencies of light;

a design formed of lines and areas upon a design back-ground;

said lines and areas being aligned with at least a portion of said conduit;

means for changing the position of said conduit at different times so that at one time a first portion of said conduit is above a second portion and at another time a second portion of the conduit is above the first portion;

a panel adjacent to the viewing surface;

a first portion of said continuous conduit being within said panel and a second portion being external to said panel;

a second panel located at an angle to said first-mentioned panel;

said second portion of said continuous conduit being within said second panel;

said viewing surface extending over said second panel; and

said means for changing position of said conduit including a means for rotating said first and second panels through at least a portion of a circle about a horizontal axis.

3. A display apparatus comprising:

a viewing surface having a design background;

at least one continuous conduit formed of a material capable of passing light;

said conduit being partly filled with a fluid capable of blocking at least some frequencies of light;

a design formed of lines and areas upon a design background;

said lines and areas being aligned with at least a portion of said conduit;

means for changing the position of said conduit at different times so that at one time a first portion of said conduit is above a second portion and at another time a second portion of the conduit is above the first portion;

a panel adjacent to said viewing surface;

said continuous conduit being entirely Within said panel;

said means for changing the position of said conduit including means for rotating said panel;

said panel including a center of rotation;

one of said first and second portions of said conduit being located radially outwardly from said center of rotation from the other portion of said conduit;

said design overlying one of said portions and the other of said portions of the conduit being relatively large; and

there being a restricted portion between said one portion and said other portion, whereby bubbles pass from said other portion to said one portion as said one portion is raised above said other portion by the rotation of said panel.

4. A display apparatus comprising:

a viewing surface having a design background;

at least one continuous conduit formed of a material capable of passing light;

said conduit being partly filled with a fluid capable of blocking at least some frequencies of light;

a design formed of lines and areas upon a design background;

said lines and areas being aligned with at least a portion of said conduit;

means for changing the position of said conduit at different times so that at one time a first portion of said conduit is above a second portion and at another time a second portion of the conduit is above the first portion;

a panel adjacent to said viewing surface;

said continuous conduit having first, second and third sections within said panel;

said first section of said continuous conduit having a first end communicating with said second section and a second end communicating with said third section;

said second section of said conduit having a first end communicating with said first end of said first section and having a second end;

said third section of said conduit having a first end communicating with said second end of said first section and having a second end;

said second ends of said second and third sections being positioned adjacent to and on opposite sides of said first section;

a tube extending partly outside of said panel and connecting said second ends of said second and third sections, whereby a continuous path in the conduit is formed that includes said tube and having at least two loops therein;

said panel having a center of rotation;

said means for changing the position including means for rotating said panel about said center of rotation, whereby one section of said continuous conduit is raised above another section at different times.

5. A display apparatus comprising:

a viewing surface having a design background;

at least one continuous conduit formed of a material capable of passing light;

said conduit being partly filled with a fluid capable of blocking at least some frequencies of light;

a design formed of lines and areas upon a design background;

said lines and areas being aligned with at least a portion of said conduit;

means for changing the position of said conduit at different times so that at one time a first portion of said conduit is above a second portion and at another time a second portion of the conduit is above the first portion;

a panel adjacent to said viewing surface;

said continuous conduit being entirely within said panel;

said means for changing the position of said conduit including means for rotating said panel;

a second panel;

a second continuous conduit entirely within said second panel;

said first and second panels being attached together;

said second continuous conduit including a liquid capable of blocking at least some frequencies of light;

said second conduit being aligned at least in one portion with said design and said first-mentioned continuous conduit;

a design sheet having translucent and opaque portions, said design sheet being positioned between and connecting said first-mentioned and second panels;

said translucent portions of said design sheet being aligned with at least a portion of said design formed of lines and areas on a design background and at least one of said continuous conduits.

6. Display apparatus comprising:

a plurality of panels;

each of said panels including a first and a second sheet formed of a material capable of passing light and an orifice means for permitting said passageways to communicate with an external source of liquid;

each of said first sheets having a plurality of continu ous channels therein;

each of said second sheets being attached to a different first sheet over said continuous channels and being sealed to the first sheet with a liquidtight seal, whereby at least one continuous passagewa is formed throlcigh said panel; one of said irst and secon sheets in each panel being adapted to have indicia for display positioned against it;

each of the panels being mounted about a single horizontal axis of rotation;

each of the panels having a passageway that communicates with the passageway of another of said panels;

said display apparatus further including a means for moving each of said panels in succession from a substantially horizontal position beneath said axis to a vertical position.

7. A display apparatus comprising:

a viewing surface having a design background;

at least one continuous conduit formed of a material capable of passing light;

said conduit being partly filled with a fluid capable of blocking at least some frequencies of light;

a design formed of lines and areas upon a design background;

said lines and areas being aligned with at least a portion of said conduit;

means for changing the position of said conduit at different times so that at one time a first portion of said conduit is above a second portion and at another time a second portion of the conduit is above the first portion;

one of said first and second portions of said conduit being adjacent to an opaque portion of said viewing surface;

at least a portion of said design being capable of passing light and including a plurality of spacedapart lines and areas on said viewing surface opposite said conduit so that light rays perpendicular to said viewing surface and passing through the lines and areas also pass through said conduit, with some of said lines extending in directions independent of the direction of the conduit and some of said lines and areas having sizes smaller than the conduit, whereby an artistic design is animated under the control of said means for changing the position of said conduit at different times.

8. A display apparatus according to claim 7 in which one of said first and second portions of said conduit includes an enlarged portion, whereby the free flow of said fluid removes bubbles from said conduit. 

1. A display apparatus comprising: a viewing surface having a design background; at least one continuous circuit formed of a material capable of passing light; said conduit being partly filled with a fluid capable of of blocking at least some frequencies of light; a design formed of lines and areas upon a design background; said lines and areas being aligned with at least a portion of said conduit; means for changing the position of said conduit at different times so that at one time a first portion of said conduit is above a second portion and at another time a second portion of the conduit is abovE the first portion; a panel adjacent to the viewing surface; a first portion of said continuous conduit being within said panel and a second portion being external to said panel; said means for changing the position of said conduit including means for raising and lowering the portion of said conduit external to said panel while said panel is stationary.
 2. A display apparatus comprising: a viewing surface having a design background; at least one continuous conduit formed of a material capable of passing light; said conduit being partly filled with a fluid capable of blocking at least some frequencies of light; a design formed of lines and areas upon a design back-ground; said lines and areas being aligned with at least a portion of said conduit; means for changing the position of said conduit at different times so that at one time a first portion of said conduit is above a second portion and at another time a second portion of the conduit is above the first portion; a panel adjacent to the viewing surface; a first portion of said continuous conduit being within said panel and a second portion being external to said panel; a second panel located at an angle to said first-mentioned panel; said second portion of said continuous conduit being within said second panel; said viewing surface extending over said second panel; and said means for changing position of said conduit including a means for rotating said first and second panels through at least a portion of a circle about a horizontal axis.
 3. A display apparatus comprising: a viewing surface having a design background; at least one continuous conduit formed of a material capable of passing light; said conduit being partly filled with a fluid capable of blocking at least some frequencies of light; a design formed of lines and areas upon a design background; said lines and areas being aligned with at least a portion of said conduit; means for changing the position of said conduit at different times so that at one time a first portion of said conduit is above a second portion and at another time a second portion of the conduit is above the first portion; a panel adjacent to said viewing surface; said continuous conduit being entirely within said panel; said means for changing the position of said conduit including means for rotating said panel; said panel including a center of rotation; one of said first and second portions of said conduit being located radially outwardly from said center of rotation from the other portion of said conduit; said design overlying one of said portions and the other of said portions of the conduit being relatively large; and there being a restricted portion between said one portion and said other portion, whereby bubbles pass from said other portion to said one portion as said one portion is raised above said other portion by the rotation of said panel.
 4. A display apparatus comprising: a viewing surface having a design background; at least one continuous conduit formed of a material capable of passing light; said conduit being partly filled with a fluid capable of blocking at least some frequencies of light; a design formed of lines and areas upon a design background; said lines and areas being aligned with at least a portion of said conduit; means for changing the position of said conduit at different times so that at one time a first portion of said conduit is above a second portion and at another time a second portion of the conduit is above the first portion; a panel adjacent to said viewing surface; said continuous conduit having first, second and third sections within said panel; said first section of said continuous conduit having a first end communicating with said second section and a second end communicating with said third section; said second section of said conduit having a first end cOmmunicating with said first end of said first section and having a second end; said third section of said conduit having a first end communicating with said second end of said first section and having a second end; said second ends of said second and third sections being positioned adjacent to and on opposite sides of said first section; a tube extending partly outside of said panel and connecting said second ends of said second and third sections, whereby a continuous path in the conduit is formed that includes said tube and having at least two loops therein; said panel having a center of rotation; said means for changing the position including means for rotating said panel about said center of rotation, whereby one section of said continuous conduit is raised above another section at different times.
 5. A display apparatus comprising: a viewing surface having a design background; at least one continuous conduit formed of a material capable of passing light; said conduit being partly filled with a fluid capable of blocking at least some frequencies of light; a design formed of lines and areas upon a design background; said lines and areas being aligned with at least a portion of said conduit; means for changing the position of said conduit at different times so that at one time a first portion of said conduit is above a second portion and at another time a second portion of the conduit is above the first portion; a panel adjacent to said viewing surface; said continuous conduit being entirely within said panel; said means for changing the position of said conduit including means for rotating said panel; a second panel; a second continuous conduit entirely within said second panel; said first and second panels being attached together; said second continuous conduit including a liquid capable of blocking at least some frequencies of light; said second conduit being aligned at least in one portion with said design and said first-mentioned continuous conduit; a design sheet having translucent and opaque portions, said design sheet being positioned between and connecting said first-mentioned and second panels; said translucent portions of said design sheet being aligned with at least a portion of said design formed of lines and areas on a design background and at least one of said continuous conduits.
 6. Display apparatus comprising: a plurality of panels; each of said panels including a first and a second sheet formed of a material capable of passing light and an orifice means for permitting said passageways to communicate with an external source of liquid; each of said first sheets having a plurality of continuous channels therein; each of said second sheets being attached to a different first sheet over said continuous channels and being sealed to the first sheet with a liquid-tight seal, whereby at least one continuous passageway is formed through said panel; one of said first and second sheets in each panel being adapted to have indicia for display positioned against it; each of the panels being mounted about a single horizontal axis of rotation; each of the panels having a passageway that communicates with the passageway of another of said panels; said display apparatus further including a means for moving each of said panels in succession from a substantially horizontal position beneath said axis to a vertical position.
 7. A display apparatus comprising: a viewing surface having a design background; at least one continuous conduit formed of a material capable of passing light; said conduit being partly filled with a fluid capable of blocking at least some frequencies of light; a design formed of lines and areas upon a design background; said lines and areas being aligned with at least a portion of said conduit; means for changing the position of said conduit at different times so that at one time a first portion of said conduit is above a second portion and at another time a second portion of the conduit is above the first portion; one of said first and second portions of said conduit being adjacent to an opaque portion of said viewing surface; at least a portion of said design being capable of passing light and including a plurality of spaced-apart lines and areas on said viewing surface opposite said conduit so that light rays perpendicular to said viewing surface and passing through the lines and areas also pass through said conduit, with some of said lines extending in directions independent of the direction of the conduit and some of said lines and areas having sizes smaller than the conduit, whereby an artistic design is animated under the control of said means for changing the position of said conduit at different times.
 8. A display apparatus according to claim 7 in which one of said first and second portions of said conduit includes an enlarged portion, whereby the free flow of said fluid removes bubbles from said conduit. 